I tried to get this article started, but I am extremely far from being anything of an expert on the matter—my experiences have been few, recent, and rather casual. The greatest weakness that I've contributed so far is to give the article a very strong North American (U.S. & Canada anyway) bias. It would be great to see the geographical scope of this article expanded. For example, I can only guess at the incredible Urbex opportunities in the FSU... --PeterTalk 19:32, 1 August 2009 (EDT)
I think we should tread very carefully with this topic and avoid posting any specific information.
Legality - Urbex mostly falls in a grey area (unless you are in Scotland, "right to wander" ahoy!) but is just as likely to be flat out illegal. Covering the latter is blatently against Wikitravel's rules. The page as it stands is treading a thin line I feel...
Ethics and preservation - I raise the above mostly as an excuse to cover the main problem: I have seen the damage over-exposure has done to specific sites. Near where I used to live, one guy started maintaining a foreign-language website stating maps, transport directions, the LOT to some amazing sites made mostly amazing by the objects left behind. Naturally, after remaining in that state for years, it took only months for the location to be picked clean by vandals.
Scope - Urbex details are way beyond the wikitravel scope as the level of upkeep required to log the rise and fall of specific sites exceeds that of logging every small bar in Tokyo. Better to have a good solid resource outlining some vaguerities, clearing up questions as to what urbex actually is, and hints on where to start looking than spreading it too thin. Part of the challenge of urbex is finding a site in the first place and pulling that aspect out of the equation will reduce any respect for the hobby. Teach a man to fish and all.